Dual inverter for counted stacks of sheets



United States Patent {72] Inventor Joseph E.Radomski Saco,Maine [21]AppLNo. 782,148 [22] Filed Dec.9,1968 [45] Patented Dec. 15, 1970 [73]Assignee Southworth Machine Company Portland, Maine a corporation ofMaine [54] DUAL INVERTER FOR COUNTED STACKS 0F SHEETS 12 Claims, 4Drawing Figs.

[52] U.S.Cl 214/1, 198/33 [51] lnt.Cl. ..B65g69/00 [50] FieldolSearchl98/33R3, 33R4;2l4/1R,1A.B., 1,310-314 [56] References Cited UNITEDSTATES PATENTS 1,677,290 7/1928 Parker 24l/l(R)UX 2,160,581 5/1939Behnke 2l4/l(R)X 2,277,310 3/1942 Engelhart 2l4/1(R)X 2,774,487 12/1956Rounsefelletall. 2l4/1(R) 2,836,282 5/1958 Rompre 2l4/l(R)X 2,984,3645/1961 Lamb 2l4/l(R) Primary ExaminerGerald M. Forlenza AssistantExaminer-F rank E. Werner Attorney-Pearson & Pearson ABSTRACT: Aninverter for sequentially inverting portions of stacked and countedpiles of paper. A paper trimmer may thus be used to full load capacitywith each trim, the inversion of each lift of untrimmed sheets, prior totrimming, retaining the count in the stack of trimmed sheets. Themachine is so constructed that two knifeloads of paper can be stored inthe same floor space as used for one knifeload in prior art devices.This result is accomplished by mounting two power actuated, movableclamping members each on an opposite side ofa fixed central clampingmember within a rotatable inverter frame. The lift-supporting faces ofall members are flat, smooth and planar whether air cushion or belt.There is a paper-receiving passage between each movable clamping memberand the fixed central member, an endless conveyor on one member in eachpassage, and the inverter is so operated that one lift of paper may bereceived in one passage at the same time another lift of paper isdischarged from the other passage.

PATENTEU UEBVII 5 mm 547279 SHEET 1 BF 2 22 @5 E O g 34 INVENTOR. JosephE. Rudomskl *Emmm ATTORNEYS PATENTEU new SIBYG SAT.

SHEET 2 OF 2 Fig. 4

INVENTOR. Joseph E. Rodomski BY RNEYS DUAL INVERTER FOR COUNTED STACKSOF SHEETS BACKGROUND OF THE INVENTION In processing paper and likematerial of a flimsy-sheet construction, it is often desired to furtherprocess paper which has been stacked and counted.

One such situation is when paper is to be unstacked by the ream, orlift, from a counted, marked stack before entering a paper-trimmingapparatus. Heretofore, it has been necessary to unstack an increment ofpaper which is exactly equal to one ream, or multiple thereof, forexample, a team of 500 sheets, at a time, using tags at each 500th sheetasguides. In such a situation, considerable trimmer capacity is likelyto go to waste. For example, suppose the guillotine trimmer has a 7 inchreceiving section, i.e., is capable of handling a 7 inch thick stack ofpaper. Suppose further that a ream of the paper being handled is 2.5inches thick. In th'ese'circumstances, the trimmer will only be loadedwith two reamsof' paper because it is the largest number of full reamsthat can be put into the machine by using the visible guide tags. Thusonly 5 inches of the 7 inch throat is utilized and nearly 30 percent ofthe true capacity of the machine is wasted. i

when the inverter of this invention is used, a partial ream load, orlift, can be processed, because'the first sheet of the next followingload will be'discharge'd from the inverter in a sequence immediatelyfollowing the sheet which was adjacent to the first sheet in theoriginal stacked and counted pile.

It is, of course, necessary to maintain thecount, yet to do so withapparatus as inexpensive and simple to maintain as possible. When largesheets of paper are to be processed, it is particularly important thatthe apparatus be reasonably compact sothat it takes as little floorspace as is possible.

SUMMARY OF THE INVENTION Therefore it is an object of the inventionto'provide an improved inverter suitable for use in processin'gsuccessive individual lifts of paper and like flimsy sheet materials.

It is another object of the invention to provide an inverter which has ahigh capacity per unit time-and requires relatively little floor space.

Another object of the invention is to provide an inverter which tends toremove air entrapped between paper sheets and thereby further augmentits capacity.

Other objects of the invention will, be obvious to those skilled in theart on reading this application.

The above objects have been achieved'by the construction of a novelinverter comprising an elongated inverter frame which is rotatablymounted for movement through an angular distance of I80 around a centrallongitudinal axis. A pair of elongated movable clamps are adapted forcompressively holding a lift (or ream) of paper against a centrallypositioned surface with side guides while inversion takes place.Preferably the central surface is an air table and the movable clampingmembers include endless conveyor belts for moving the reams into and outof the inverter.

However, in some embodiments of the invention, the centrally positionedclamping surface can be a dual-faced conveying surface (for example anendless belt adapted for two-way operation) and the air surface can beon the paper-contacting face of the movable, paper-positioning, clampingmembers.

FIG. 1 is an end elevation, partly in section, of the inverter of theinvention.

FIG. 2 is a diagrammatic view, on a the stabilizer means.

reduced scale, showing FIG. 3 is a side elevation, partly in section, ofthe inverter includes an elongated frame 21, supported for turningthrough I an angle of 180 on. a base 22 by the single, partly circular.wheel 23 and the central hollow bearing 24 gated, dual-faced, table 25,fixed along the central longitu-- dinal axis 29 of the frame 21, whichforms a pair of loadreceiving passages 26 and 27, each on an oppositeside of the axis. It is thus possible to eliminate one of theconventional wheels and rely on a single wheel 23, plus the upstandingbase member 28 in which the hollow bearing 24 is journalled forrotation. It will be obvious that two wheels canbe used if desired. I

The wheel 23 is rotatably supported in a pair of friction rolls 31 and32, the rolls being driven by sprockets 33 and chain 34 from areversible motor and reducer 35 in a known manner, so that the wheel andframe are tumable through a half circle.

Preferably the fixed table 25 is of the air flotation type with oppositeupper and lower lift support faces 36 and 37, each having a multiplicityof air apertures, 38 or 39, fed by transverse hollow conduits 42 or 43.The hollow conduits 42 and 43 are each connected to one of the oppositeends 44 or 45 of a plenum 46, the plenum being connected centrallythrough hollow bearing 24 and hollow upright28 to a source of air underpressure, such as the air pressure blower 47, carried on base 22, or tomill air supply.

Valve means in the form of a ball 51, valve seat 52 and inclined balltrack 53 are provided in each end 44 or 45,'of plenum 46 so that theball 51 will roll down the track 53 by gravity to close seat 52 and shutoff air to the apertures of the lower face each time the inverter frameis turned. Thus full air pressure is emitted from the upper face airoutlets 38, to air float a lift being received on the then upper liftsupport face 36 or 37 and no pressure is lost through the lower airoutlets, not then being used.

A pair of elongated movable clamps; or jaws, are mounted in inverterframe 21, each clamp 54 or 55 having a paper-positioning surface 56 or57 substantially coextensive in area with, and in parallelism with, theadjacent face 36 or 37 of the fixed air flotation table 25.Preferably,'each surface 56 or 57 is a conveyor surface formed by anendless belt such as 58 or 59, trained over a multiplicity ofbelt-carrying rolls 60 or 61, the end rolls 62 or 63 of each set beingcrowned to prevent side creep of the belt and being a driveroll,'rotated by one of the drive motors 64 or 65. It will be noted thatno tracks rollers, pallets or trays are used in the inverter 20 of theinvention, the lift of counted sheets being contacted and supported onlyby the flat, smooth, planar, lift support faces 36, 37, 56 and 57, toavoid damage or marking of limp lift of limp sheets.

The drive motors 64 and 65 are preferably reversible and it will be seenthat the dual passages, or zones, 26 and 27, are each thus defined by afixed, inner, air flotation face 36 or 37 and a movable, outer, powerbelt, conveyor surface 56 or 57, all en extending from one end 67 to theother end 68 of the frame 21. Flexible conduits 69 and 70 connect motors64 and 65 to fixed table 25 for connection to the control system 71 of Ithe inverter.

The frame 21 is skeletonized and consists, in general, of the upperrectangular, horizontal frame 72, the lower horizontal frame 73, and thecentral table 25, these all being fixed and immovable relative to wheel23. A pair of upstanding frame pieces 74 and 75 fixedly connect one end67 of the frame and a second pair of upstanding frame pieces 76 and 77fixedly connect the other end 68 of the frame, these frame pieces 74,75, 76 and 77 being gear racks.

Two-way stabilizer means 78 (FIG. 2) is provided in the form of piniongears 79 on each opposite side of each end of each movable clamp, whichgears are enmeshed in their respective gear racks. The gears 79 on eachopposite side are each fast to a transverse shaft 80, and the shafts ateach end of each clamp carry sprockets 81 connected by a longitudinallyextending chain 82. Thus the clamp members remain in parallelism andcannot tilt as they move toward and away from the adjacent face of thefixed table 25.

Each clamp member, or movable jaw, 54 or 55 includes a longitudinallyextending brace 85 centrally thereof, the brace being connected to apiston rod 86, of a fluid pressure cylinder 87, the cylinder being fastto a suitable bracket 88 on wheel 23. The clamp moving, or actuation,means 86 and 87 is powered from a suitable pressure source, or millsupply, and controlled by the control system 71 of the invention. Qltwill be understood that the surfaces 56 and 57 of the movable clamps 54and 55 could be air flotation surfaces if desired, and that the faces 36and 37 of the table 25 could be formed by the upper and lower stretchesof an endless driven conveyor belt if desired.

"in operation, as best shown in FIG. 4, the inverter 20 may be locatedbetween a guillotine trimmer 90 and a movable uns 'tacker 91 of awell-known type, the upper face 36 of table 25 being at the level of theair table of the unstacker for loading.

The level ofeach successive lower conveyor face 56 or 57 is at the levelof the deck 92 of the trimmer, so that a lift of paper in the lowerpassage 27 may be discharged by the belt onto the deck. The unstacker91, in a known manner, penetrates into a 'c'o'unted stack 93, tosegregate successive topmost lifts, or reams, such as 94, draw the liftonto the unstacker, move to the inverter 20 and roll convey the liftonto the upper air flotation surface 36 in upper passage 26. The controlsystem 71 then causes the inverter to turn sufficiently to slide thelift sidewise against the vertical flat bars 98 serving as side guidesto keep the edges of the sheets aligned, whereupon the clamp 5.4.or 55closes to hold the lift tightly during the remainder of the l80 turn.Suitable limit switches and photo cells cause the inverter to halt, theclamp 54 to open to the level of the trimmer deck, and the conveyor beltto discharge the lift onto the deck. Meanwhile another lift is beingadvanced into the :thenuppeipassage, so that the inverter 20 is alwayshandling two lifts in the floor space required by one lift.

Regardless of the number of sheets in each lift, and preferably thiswill be the maximum number capable of being handled in the trimmer, thecount of the stack is not lost, because each lift is being invertedprior to being trimmed for restacking in the exact sheet order of theoriginal untrimmed stack. The final trimmed and reassembled pile, orstack, will be inverted from the original, but the count will have beenretained.

glclaim: 1. in an inverter suitable for the sequential inverting oflifts 'ofgpaper andof the type comprising paper-receiving means ina-frame rotatably mounted on a central longitudinal axis for back andforth motion through a 180 angle, the improvement consisting of: v

a dual-faced, back to back centrally located air table fixed in saidframe, each'said face being flat, smooth and planar to support a liftand including a plurality of air supply outlets for air cushion supportof said lift;

two paper-positioning clamps, each mounted within said frame and eachmounted opposite one face of said table,

for clamping movement toward and away from said face,

' said clamps each including a flat, smooth, planar, conveyor belt,lift-clamping surface and powered actuating means for reciprocal movingsaid lift-clamping conveyor belt surface towards and away from a face ofsaid table thereby forming means to firmly clamp and release a lift ofpaper therebetween;

t'wo axially extending through passages in said frame, each defined byone said clamping surface of a paper-positioning clamp and the adjacentlift-supporting face of said dual-faced table; and

Fpower means, operably connected to each said conveyor belt surface onsaid clamps for moving a lift axially through one of said zones.

-2. The inverter of claim 1 wherein each said power driven c'o'n'veyingsurface consists of series of rolls, an end roll of the series being acrowned drive roll, and an endless belt trained th erearound.

3. The inverter of claim 1 wherein said air table includes gravityactuated valve means for carrying air from an air supply source to theoutlets in the face of said air table which is facing upwardly.

4. The inverter of claim 1 plus two-way stabilizer means on each saidclamp, said means including gear racks at each end of said clamps oneach opposite side thereof, and gears intermeshed therein for preventinglateral, or longitudinal, tilt of said clamps.

5. In an inverter of the type having an elongated frame turnable on acentral longitudinal axis through an angular distance of on a base,the'combination of:

an elongated table located centrally in said frame along said axis, saidtable having a pair of back to back opposite axially extending flat,smooth, planar lift support faces thereon;

a pair of elongated clamps, each having a flat, smooth, planar liftsupport face extending in parallelism with one of said table faces at aspaced distance therefrom, to form a pair of axially extending throughpassages in said frame, each on an opposite side of said axis andextending from end to end of said frame, one lift support face in eachsaid passage being mounted for movement toward and away from the otherlift support face thereini power means for moving the movable supportfaces toward and away from the other support faces therein to clamp alift of flimsy paper sheets therebetween; and at least one said supportface in each said passage being formed by an endless belt power conveyormeans for moving a lift of paper longitudinally therealong.

6. An inverter as specified in claim 5, wherein:

a said frame includes a single, centrally located, partly circular,wheel turnable in a pair of rolls in the inverter base;

a hollow bearing, at the center of one end of said fixed tablejournalled on said base, and

said table is an air cushion table supplied with pressurized air throughsaid hollow bearing.

7. An inverter as specified in claim -5, wherein each said lift supportface of said table includes air apertures, said table constitutes aplenum connecting said apertures to a source of air pressure and saidplenum includes automatic, gravity actuated valve means disconnectingair from the apertures on each successive bottom-most lift support face.

8. An inverter as specified in claim 5, wherein:

said table is an air table connected to a source of air, and

having air outlets in said faces;

each said clamp includes said endless belt power conveyor means formingthe lift support surface thereof; and

whereby a lift may be slid into the upper said passage on an air cushionsurface of said fixed table, clamped, turned and unclamped by saidinverter, and conveyed out of said passage on the conveyor means of thelift support face forming said passage.

9. An inverter as specified in claim 5, wherein:

each opposite end of said movable lift support face is positivelyconnected by intermeshed gear and gear rack stabilizer means to theother end of the movable lift support face of the said clamp on eachopposite side thereof; and

whereby both lateral and longitudinal stability of said movable clampsis assured.

10. An inverter for interposition between an unstacker and a papertrimmer deck, for receiving successive lifts of counted sheets,inverting each lift through 180, and is discharging the means mountingbelts surfaced clamp jaw for movement toward and away from the fixedjaws;

one said air flotation faced jaw being adapted to slidably receive alift of counted sheets at one predetermined level while one saidbelt-surfaced clamp jaw is in position to discharge the previous liftonto said trimmer deck at another, different, predetermined level 11. Aninverter for counted, marked lifts of paper sheets,

said inverter comprising:

an elongated inverter frame, rotatably mounted on a base, for turningalongitudinal axis through an' angular distance of at least 180;

an air table fixed centrally and diametrically of said frame, said tablehaving a pair of back to back oppositely disposed, flat, smooth, planarair flotation faces, each on an opposite side of axis;

a pair of movable lift-positioning clamp jaws each mounted on said frameopposite one of said air flotation faces for movement toward and awaytherefrom and each having a flat, smooth, planar conveyor belt face ingeneral parallelism therewith for mutually defining one of a pair oflongitudinally axially extending passages'in said frame;

power means for moving said lift-positioning clamp jaws toward and awayfrom the air flotation faces of said table to clampa lift therebetweenfor turning; and

power means for turning said frame on said axis to invert eachsuccessive lift enclosed in one of said passages and power means formoving said conveyor belt faces to move an unclamped lift axiallythrough said inverter.

12. In an inverter of the type having an elongated frame tumable on acentral longitudinal axis through an angular distance of l on a base,the combination of:

an elongated table located in said frame along said axis, said tablehaving a pair of back to back opposite flat, smooth, planar lift supportfaces thereon;

a pair of elongated clamps, each having ,a flat, smooth,

planar lift support face extending in parallelism with one.

of said table faces at a spaced distancetherefrom, and opposed thereto,to form a pair of axially extending through passages in said frame, eachon an opposite side of said axis and extending from end to end of saidframe;

at least one lift support face in each said passage being fixed and theother being movable toward and away therefrom;

power means for moving the movable'support face toward and away from thefixed support face, in each said passage, to clamp a lift of flimsypaper sheets therebetween; and t power endless belt conveyor meansforming at least one of said opposed flat, smooth, planar support facesin each passage for moving a lift of paper longitudinally therealong.

